Vulnerability Database

374,078

Total vulnerabilities in the database

CVE-2023-53199 — linux / linux_kernel

Missing Release of Resource after Effective Lifetime

In the Linux kernel, the following vulnerability has been resolved:

wifi: ath9k: hif_usb: clean up skbs if ath9k_hif_usb_rx_stream() fails

Syzkaller detected a memory leak of skbs in ath9k_hif_usb_rx_stream(). While processing skbs in ath9k_hif_usb_rx_stream(), the already allocated skbs in skb_pool are not freed if ath9k_hif_usb_rx_stream() fails. If we have an incorrect pkt_len or pkt_tag, the input skb is considered invalid and dropped. All the associated packets already in skb_pool should be dropped and freed. Added a comment describing this issue.

The patch also makes remain_skb NULL after being processed so that it cannot be referenced after potential free. The initialization of hif_dev fields which are associated with remain_skb (rx_remain_len, rx_transfer_len and rx_pad_len) is moved after a new remain_skb is allocated.

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

  • Published: Sep 15, 2025
  • Updated: Dec 4, 2025
  • CVE: CVE-2023-53199
  • Severity: Medium
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: Medium
  • Score: 5.5
  • AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CWEs:

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.